Post on 12-Feb-2018
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BMAT Physics Skills Tested
A quick summary in the order of the following questions on the main topics tested by BMAT.
Newton’s laws, Graphs of Motion and Definitions
F = ma
Distance = area under a v‐t graph
Acceleration = gradient of v‐t graph
Connected things all move with the same acceleration (the train)
Momentum
Force x Time = change of momentum (mv)
Work Energy Power
Calculating KE and GPE
Interchange of these e.g. when something falls, all its GPE turns into KE
Power = E/t
Work done = F x d (if d is in line with F)
Knowing that work done is energy transferred: so when a force stops something, its energy is
transferred away by a force working through a given distance
Conservation of Energy when there is work done against friction
Understanding that when KE and GPE interchange there might also be energy transferred into heat
by friction; working out how much by using work done (Fxd). For example, something falling with
friction: GPE lost = KE gained + heat loss; mgh = ½ mv2 + Fd
Remembering in this that d is measured in the direction moved but h is measured vertically
Motion with drag
The idea of terminal velocity; in particular, that when you are going at that speed, the air resistance
equals your weight.
Note that with or without the parachute, it’s the same force. In free‐fall, that size of force comes
from a high speed, small area; with the parachute open, the same force is caused by small speed,
large area. (Hence in the graphs question the answer is A).
Understanding that acceleration has nothing to do with your current motion; it tells you how your
motion will change. Hence the acceleration when you open the parachute is upwards (slowing you
down) while you are still actually moving downwards.
Moments/levers
Balanced moments
Remembering that the d in moment = Fd has to be measured perpendicular to the force line.
Muscle questions: fulcrum means pivot and is always at the joint; the muscles attach close to but not
at the joint; the muscle force is called the effort. The hardest thing to spot is that the load is the way
the external object pushes on the limb e.g. the floor pushes on the foot.
Radioactivity
Half life from data or graph
Penetration to determine which radiation reaches which detectors
Decay equations – working out atomic and mass numbers e.g. when radiation is emitted
Waves
Speed = distance/ time as usual for energy transmitted by the wave
Reading graphs: period from time graphs and wavelength from distance ones
v = f x lambda
Refraction changes wavelength (and speed) but not frequency; frequency is determined by the
vibrations of the source so can never change in transit.
Blue bends best (and beta bends best in radiation, although it hasn’t been asked)
Dc Circuits
Ohm’s law and definitions for V and I
Circuit rules especially parallel combinations and short circuits (or breaks). Two bits of AS physics
would be useful extra learning: combining parallel resistors and the idea of potential at a point.
For circuit changes especially short circuits and switches, try drawing the circuit how it effectively is
before and after the change e.g. if a lamp blows, that part of the circuit is gone so re‐draw without it.
Electrical power as VI, V2/R and I2R. Determine which thing is constant when they describe making a
change and use the formula that has the constant thing and the thing you know in it.
Pressure and Density
Basic use of p=F/A and simple hydraulics
Simple density of objects (possibly mixtures so check you understand proportion by mass or by
volume)
BMAT Physics Practice Booklet Newton’s laws, Graphs of Motion and Definitions 2006
2009 past paper
2009 past paper
2010 past paper
Momentum Specimen 2005
2008
Work, Energy and Power 2003
2005
Specimen 2005
2009 past paper
2010 past paper
2013 past paper
2011 past paper
2012 past paper
Conservation of Energy when there is work done against friction New specimen 14 repeat of 2011 past paper
2012 past paper
2010 past paper
Motion with drag 2004
2008
New specimen 14 repeat of Specimen 2005 (itself a slight modification of 2003 – option Eadded)
2009 past paper
Moments/levers 2003
2005
Undated ‘past paper’ – same as 2007
2004
2008
Undated ‘past paper’ – same as 2007
2003
Radioactivity 2010 past paper
Undated ‘past paper’ – same as 2007
2011 past paper
New specimen 14 – same as 2013 past paper Q15
2012 past paper
2003
2012 past paper
2004
2010 past paper
2005
2008
2006
2009 past paper
2005
2003
2008
Waves 2008
New specimen 14 same as 2010 past paper
New specimen 14 same as 2012 past paper
Undated ‘past paper’ – same as 2007
2003
2011 past paper
2009 past paper
2003
2006
2006
2005
2012 past paper
2011 past paper
2013 past paper
2013 past paper
Heat Energy New specimen 14
Undated ‘past paper’ – same as 2007
Transformers New specimen 14 – same as 2007 (undated paper) Q7 (with MCQ options added)
Specimen 2005
2003 – a one‐off on generators
Electricity – dc circuits
2003
Specimen 2005
2010 past paper
Specimen 2005
2011 past paper
2013 past paper
2008
2006
2013 past paper
2005
2004
2011 past paper
2012 past paper
2009 past paper
2006
2003
Pressure, Density etc. 2005
2013 past paper
2012 past paper
Specimen 2005
2006
Other 2013 past paper 23 Consider this graph